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The INKEY List Ceramide Serum Versus The Ordinary Amino Acids + B5

The INKEY List Ceramide Serum Versus The Ordinary Amino Acids + B5 This barrier-repair treatment is formulated around Sodium Hyaluronate and Ceramide NP to strengthen the skin barrier and hydrate skin. This hydrating serum is formulated around Sodium PCA and P

The INKEY List Ceramide Serum Versus The Ordinary Amino Acids + B5

This barrier-repair treatment is formulated around Sodium Hyaluronate and Ceramide NP to strengthen the skin barrier and hydrate skin.

This hydrating serum is formulated around Sodium PCA and Panthenol to hydrate skin and strengthen the skin barrier.

What's inside

Key Ingredients

No key ingredients

Benefits

Concerns

Ingredients Side-by-side

Water

Butylene Glycol

Glycerin

Sodium Hyaluronate

Simmondsia Chinensis Seed Oil

Carbomer

Phenoxyethanol

Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer

Benzyl Alcohol

Squalane

Sodium Lauroyl Lactylate

Sodium PCA

Sodium Hydroxide

Sodium Stearoyl Glutamate

Sodium Lactate

Arginine

Aspartic Acid

Ethylhexylglycerin

Sodium Gluconate

PCA

Polysorbate 60

Dehydroacetic Acid

Ceramide NP

Glycine

Alanine

Sorbitan Isostearate

Ceramide AP

Phytosphingosine

Serine

Cholesterol

Valine

Xanthan Gum

Isoleucine

Proline

Threonine

Histidine

Phenylalanine

Ceramide EOP

Water, Butylene Glycol, Glycerin, Sodium Hyaluronate, Simmondsia Chinensis Seed Oil, Carbomer, Phenoxyethanol, Hydroxyethyl Acrylate/Sodium Acryloyldimethyl Taurate Copolymer, Benzyl Alcohol, Squalane, Sodium Lauroyl Lactylate, Sodium PCA, Sodium Hydroxide, Sodium Stearoyl Glutamate, Sodium Lactate, Arginine, Aspartic Acid, Ethylhexylglycerin, Sodium Gluconate, PCA, Polysorbate 60, Dehydroacetic Acid, Ceramide NP, Glycine, Alanine, Sorbitan Isostearate, Ceramide AP, Phytosphingosine, Serine, Cholesterol, Valine, Xanthan Gum, Isoleucine, Proline, Threonine, Histidine, Phenylalanine, Ceramide EOP

Propanediol

Betaine

Panthenol

Lysine Hcl

Glutamic Acid

Citric Acid

Dimethyl Isosorbide

Polysorbate 20

Trisodium Ethylenediamine Disuccinate

1,2-Hexanediol

Caprylyl Glycol

Water, Propanediol, Betaine, Sodium PCA, Panthenol, Sodium Lactate, Arginine, PCA, Aspartic Acid, Glycine, Alanine, Serine, Threonine, Valine, Proline, Isoleucine, Lysine Hcl, Histidine, Phenylalanine, Glutamic Acid, Citric Acid, Dimethyl Isosorbide, Polysorbate 20, Trisodium Ethylenediamine Disuccinate, 1,2-Hexanediol, Caprylyl Glycol

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Alternatives

Ingredients Explained

These ingredients are found in both products.

Ingredients higher up in an ingredient list are typically present in a larger amount.

Alanine is an amino acid and is already found in the human body. Our skin uses alanine to build collagen, elastin, and keratin.

Arginine is a semi-essential amino acid. This just means our bodies can product a bit on its own, but sometimes needs a little boost from food sources.

It is a part of your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Here's an interesting thing about Arginine: your skin converts it into urea through the Krebs-Henseleit urea cycle. Urea is one of the most effective humectants your skin naturally produces.

A clinical study showed applying 2.5% arginine hydrochloride to atopic dermatitis skin showed significant urea levels in the stratum corneum and improved moisture in just four weeks.

Arginine is also a precursor to nitric oxide; nitric oxide improves microcirculation and supports wound healing and collagen synthesis.

One study found that an amino acid complex containing Arginine reduced skin irritation, improved hydration, and accelerated skin repair in clinical / in-vivo studies.

Arginine itself is an amino acid and not a fatty acid, oil, or ester. On its own, it's not a direct food source for Malassezia, or the yeast that causes fungal acne.

Aspartic Acid is an amino acid that our bodies produce naturally. It is an antioxidant.

Our body uses Aspartic Acid to help build collagen and elastin. It also plays a role in hydrating skin.

Glycine is the smallest amino acid and a key building block of collagen. It's part if your skin's Natural Moisturizing Factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

A study from 2022 found that an amino acid complex featuring taurine, arginine, and glycine significantly reduced skin irritation, improved redness, and accelerated the skin repair process.

Histidine is a semi-essential amino acid used by our bodies to create protein. It has humectant and skin conditioning properties.

Our bodies use histidine to create filaggrin - filaggrin is a structural protein that the skin uses in maintaining skin barrier.

One study found histidine and carnosine to be a dynamic duo for your skin:

Oral histidine has also been found to help with filaggrin-deficit skin disorders such as atopic dermatitis.

Why is it considered a semi-essential amino acid? This is because adults are able to create it but children must get it from their diet.

Isoleucine is an amino acid that helps reinforce our skin barrier. This amino acid plays a role in creating protein for the body.

Fun fact: Isoleucine is found in meat, fish, dairy, legumes, and nuts.

PCA is an amino acid derivative and one of the star players in your skin's own Natural Moisturizing Factor (NMF).

The NMF is the built-in cocktail of small molecules that keeps your outer layer of skin hydrated and your body makes it naturally.

This is why it works so well topically; PCA is a humectant that holds water in the stratum corneum and studies link higher skin PCA levels to better hydration + lower water loss. Interestingly, people show more PCA in summer and in normal vs dry skin.

Most of the benefits of this ingredient are related to hydration, softness, and barrier support.

A long-running review found that formulas with at least 2% PCA or its salts improved dry skin over both the short and long term. And the zinc salt is also used for its mild antimicrobial and astringent properties.

The salt forms are more common in cosmetics (like sodium PCA).

This ingredient is compatible with basically everything and pairs well with other humectants like glycerin or hyaluronic acid.

Usage-wise, it's typically used at low percentages (~0.2-2%).

The Cosmetic Ingredient Review Expert Panel has concluded PCA and its salts are safe as used and is non-irritating on skin even at high concentrations.

Phenylalanine is an amino acid. It is a skin soothing and hydrating ingredient. Amino acids play a crucial role in wound healing and skin hydration.

This ingredient is also used to help even out skin tone due to its ability to disrupt the melanin production process.

Two structures of phenylalanine exist: L-phenylalanine and D-phenylalanine. L-phenylalanine is essential, this means our bodies cannot produce it naturally and we must get it from foods. Our bodies convert D-phenylalanine to neurotransmitters, and D-phenylalanine is found in our bodies naturally.

Some foods that contain L-phenylalanine include eggs, soybeans, beef, milk.

Proline is a non-essential amino acid, meaning your body can make it on its own. In skincare, it is a skin conditioning ingredient that keeps skin soft and hydrated.

It makes up about 23% of the collagen molecule (collagen is the protein responsible for keeping your skin firm) and is involved in your skin's natural hyaluronic acid production. When applied topically, proline can penetrate the skin fairly well due to its small molecular size.

Reviews of this ingredient have found it to be neither a dermal irritant nor a sensitizer.

Fun fact: Proline can be found in protein-rich foods like meat, fish, eggs, and dairy.

Serine is a non-essential amino acid (your body makes it on its own!). It is a major player in your skin's natural moisturizing factor (NMF), or the water-loving molecules in your outermost layer of skin (stratum corneum) that keeps everything hydrated and happy.

Serine is one of your NMF's most abundant components that works as a skin-identical humectant. Its hydroxyl group grabs onto water molecules to boost hydration without any heaviness or occlusion.

Research on a hydrogel with serine confirmed this serine got delivered to your stratum corneum and demonstrated enhanced skin moisturization.

Interestingly serine also helps your skin produce filaggrin, a protein that keeps your skin barrier strong and used to create collagen.

Sodium Lactate is the sodium salt of lactic acid, an AHA. It is a humectant and sometimes used to adjust the pH of a product.

This ingredient is part of our skin's NMF, or natural moisturizing factor. Our NMF is essential for the hydration of our top skin layers and plasticity of skin. NMF also influences our skin's natural acid mantle and pH, which protects our skin from harmful bacteria.

High percentages of Sodium Lactate can have an exfoliating effect.

Fun fact: Sodium Lactate is produced from fermented sugar.

Sodium PCA (the salt of PCA) is one of the most well-established humectants in skincare.

Why is it so special? Your skin already makes it naturally; it's a natural component of your skin's Natural Moisturizing Factor (NMF), or the mix of water-binding compounds inside your skin cells that keeps things soft and hydrated.

As a cosmetic ingredient, it grabs water and holds it in the upper layers of skin to smooth roughness and ease dehydration.

There's some clinical support for the NMF approach with a study showing that a cream built to mimic the skin's NMF significantly boosted hydration.

Safety-wise, this ingredient non-irritating, non-comedogenic, and non-phototoxic in testing, with minimal skin absorption.

It also works really well with other hydrators like glycerin or hyaluronic acid, and typical usage is somewhere between 0.2-4%.

Threonine is an amino-acid. It helps hydrate the skin and has antioxidant benefits.

Our skin uses threonine for creating collagen and elastin. Humans are not able to create threonine and must get it through eating foods such as fish, lentils, poultry, sesame seeds, and more.

Valine is one of the essential amino acids (meaning your body can't make it on its own and has to get it from food).

In skincare, it's usually synthetically-made or pulled from plant proteins like soy.

It's one of the small building blocks that make up your skin's natural moisturizing factor (NMF), or the built-in system that helps skin hold onto water. So its main job in a formula is to give the skin gentle hydration and help it feel more comfortable.

Typical amounts are very tiny: roughly 0.00004%-0.5% in leave on products and up to 1% in rinse-off ones.

The Cosmetic Ingredient Review panel has looked at this ingredient and found no evidence of it being a skin irritant or allergen at cosmetic levels.

Water. It's the most common cosmetic ingredient of all. You'll usually see it at the top of ingredient lists, meaning that it makes up the largest part of the product.

So why is it so popular? Water most often acts as a solvent - this means that it helps dissolve other ingredients into the formulation.

You'll also recognize water as that liquid we all need to stay alive. If you see this, drink a glass of water. Remember to stay hydrated!

Similar Comparisons

The reference edit

Ingredients, questions
& further reading.

Connected source records selected through this article’s public topic index.

01

Formula cabinet

Ingredients & structured notes

Ingredient index

Ingredients Side-by-side

  1. 01Water
  2. 02Dicaprylyl Carbonate
  3. 03Glycerin
  4. 04Niacinamide
  5. 05Propanediol
  6. 06Betaine
  7. 07Polyglyceryl-4 Isostearate
  8. 08Coco-Caprylate/Caprate
  9. 09Magnesium Sulfate
  10. 10Glycosphingolipids
  11. 11Glycolipids
  12. 12Sodium Benzoate
  13. 13Disteardimonium Hectorite
  14. 14Oleic Acid
  15. 15Potassium Sorbate
  16. 16Citric Acid
  17. 17Polyglycerin-3
  18. 18Water, Dicaprylyl Carbonate, Glycerin, Niacinamide, Propanediol, Betaine, Polyglyceryl-4 Isostearate, Coco-Caprylate/Caprate, Magnesium Sulfate, Glycosphingolipids, Glycolipids, Sodium Benzoate, Disteardimonium Hectorite, Oleic Acid, Potassium Sorba…
  19. 19Caprylic/Capric Triglyceride
  20. 20Butyrospermum Parkii Butter
Source · skinsort.com
02

Product index

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03

Comparison edit

Read side by side